In response to disturbances, we can postulate two fundamentally different kinds of community response according to the type of competitive relationships exhibited by the component species - founder controlled and dominance controlled (Yodzis, 1986). Founder-controlled communities will occur if a large number of species are approximately equivalent in their ability to colonize an opening left by a disturbance, are equally well fitted to the abiotic environment and can hold the location until they die. In this case, the result of the disturbance is essentially a lottery. The winner is the species that happens to reach and establish itself in the disturbed location first. The dynamics of founder-controlled communities are discussed in Section 16.7.4.
Dominance-controlled communities are those where some species are competitively superior to others so that an initial colonizer of an opening left by a disturbance cannot necessarily maintain its presence there. In these cases, disturbances lead to reasonably predictable sequences of species because different species have different strategies for exploiting resources - early species are good colonizers and fast growers, whereas later species can tolerate lower resource levels and grow to maturity in the presence of early species, eventually out-competing them. These situations are more commonly known by the term ecological succession, defined as the nonseasonal, directional and continuous pattern of colonization and extinction on a site by species populations.
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